1. Field of the Invention
The invention relates to a mechanically operated sliding saddle disc brake comprising a fixedly positioned brake carrier, a brake saddle mounted in the brake carrier and slidably displaceable parallel to the rotational axis of the wheel to be braked, with two shanks which straddle a brake disc which is rotationally fast with the wheel, a piston mounted in the first brake saddle shank slidably displaceable parallel to the rotational axis of the wheel, which piston is connected to a pressure plate, a first brake lining carrier positioned on the pressure plate which carries a brake lining to be brought into engagement on the one side of the brake disc, a mechanically operated expansion mechanism supported on the piston and on the first brake saddle shank, a second brake lining carrier positioned on the second brake saddle shank which carries a brake lining which can be brought into engagement with the other side of the brake disc, and guides positioned on the brake carrier for guiding and supporting the two brake lining carriers.
2. Description of the Prior Art
If in such a known sliding saddle disc brake the expansion mechanism is operated, then first the piston is displaced in the first brake saddle shank, until the first brake lining, which is positioned on the first brake lining carrier connected to the piston, engages the brake disc. Due to the reaction forces exerted by the expansion mechanism, the whole of the brake saddle is then displaced in the opposite direction relative to the brake carrier, until the brake lining on the second brake lining carrier connected with the second brake saddle shank engages the opposite side of the brake disc. Due to the elastic deformability of the brake saddle this produces a slightly skew position of the second brake saddle shank, which results in irregular wear of the second brake lining in relation to its whole surface. As can easily be seen, due to the deformation or skew positioning respectively of the second brake saddle shank the region of the second brake lining closer to the rotational axis suffers less wear than the more remote region.
The wear situation for the first brake lining carrier however is different from that for the second brake lining carrier. Here the situation of forces acting, comprising the moment of the braking force at the surface of the first brake lining and the distance to abutment on the pressure plate, causes one sided lining wear on the running-in side of the brake disc.